|
 |
ORIGINAL ARTICLE |
|
|
|
Year : 2020 | Volume
: 24
| Issue : 3 | Page : 163-167 |
|
Assessment of BTX concentration around fuel station in Eastern Province Kingdom of Saudi Arabia
Khaled F Salama1, Eltigani O. M. Omar2, Mubashir Zafar2
1 Department of Environmental Health, College of Public Health, Imam Abdul Rahman Bin Faisal University, Dammam, Kingdom of Saudi Arabia 2 Department of Public Health, College of Public Health, Imam Abdul Rahman Bin Faisal University, Dammam, Kingdom of Saudi Arabia
Date of Submission | 28-Jun-2019 |
Date of Decision | 16-Mar-2020 |
Date of Acceptance | 01-Apr-2020 |
Date of Web Publication | 14-Dec-2020 |
Correspondence Address: Dr. Mubashir Zafar Department of Public Health, College of Public Health, Imamm Abdul Rehman Bin Faisal University Kingdom of Saudi Arabia
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/ijoem.IJOEM_157_19
Aim: The aim of this study is to determine the benzene, toluene, and xylenes (BTX) concentration levels in and around fuel station and its expected health risks in the City of Dammam and Al-Khobar, Saudi Arabia. Method: Forty fuel dispensing facilities were randomly selected on the basis of three different areas, residential, traffic intersection, and petrol pump locations (refueling stations). coconut shell charcoal cartridges were used for samples collection and portable Ambient Analyzer was used for measuring BTX (benzene, toluene, and xylenes) concentration. Results: Results show that the average concentration of benzene, toluene, and xylenes level around fuel stations was 10.30, 4.09, and 2.47 ppm, respectively. All means of concentration values of BTX around residential, traffic intersection, and fuel stations are exceeding the limits of air quality standards values (P < 0.01). The mean concentration of BTX around residential area, side street, and direct street was benzene 8, 12.2, and 11.5 ppm, toluene 2.5, 5.95, and 3.37 ppm, and xylenes 2, 2.13, and 2.7 ppm. Hazard Quotient (HQ) was more than >1 which showed that carcinogenic probability has increased those exposed to this toxic chemical. Conclusion: Ambient concentration of BTX was high compare to neighboring residential area and 100 m from the fuel station which can negatively affect on health of several residences. The Environmental contamination associated with BTX in petrol fuel stations impulses the necessity of preventive programs to reduce further air quality deterioration and reduce the expected health risks.
Keywords: Air, benzene, gasoline, pollution, xylenes
How to cite this article: Salama KF, Omar EO, Zafar M. Assessment of BTX concentration around fuel station in Eastern Province Kingdom of Saudi Arabia. Indian J Occup Environ Med 2020;24:163-7 |
How to cite this URL: Salama KF, Omar EO, Zafar M. Assessment of BTX concentration around fuel station in Eastern Province Kingdom of Saudi Arabia. Indian J Occup Environ Med [serial online] 2020 [cited 2021 Jan 19];24:163-7. Available from: https://www.ijoem.com/text.asp?2020/24/3/163/302815 |
Introduction | |  |
Fuel stations are the main source of gasoline vapors’ emissions which is the major sources of air pollutants. In the atmosphere around fuel service station, there are various volatile aromatic hydrocarbons (VAHs) present due to emissions of vapors through activity such as dispensing and transportation of petrol.[1],[2] The main components of VAHs are benzene, toluene, and xylenes which are called as BTX compounds.[3] In Saudi Arabia, fuel dispensing facilities are located around houses, schools, and hospitals particularly in urban areas of country.[1]
The common sources of emission of benzene, toluene, and xylenes compounds are the vehicles on the roads and fuel stations. Among BTX, xylene is the most dangerous to human health.[2],[3],[4] Fuel and gas products have high concentration BTX which emitted in the form of vapor in the environment. The common sources of these volatile organic compounds (VOCs) were gasoline vapor emission and motor vehicle exhaust.[5]
BTX also plays an important role in the atmospheric chemistry. It has been recognized as an important photochemical precursor for tropospheric ozone and second organic aerosols.[6]
Different studies found that the concentration of benzene was 89.09%, xylenes was 252%, and toluene was 239% in the fuel compared to normal threshold level.[7] Benzene and ethylbenzene are well-known carcinogens to human body.[8] Population which are living near the petrol pump stations were directly exposed to BTX. These toxic products are volatile organic compounds which are commonly called BTX.[9] These toxic compounds were classified as group 1 and 2b carcinogens.[10] Various studies were conducted in European countries to determine the organic compound emissions from gas stations and assessing control systems to prevent emissions[11],[12] and to study their expected health risks on workers.[13]
There are various health disorders due to exposure of these toxic organic compounds[14] such as neurological disorders, cancers, and teratogenic effects. The main route of entry is inhalation or ingestion. The most common health impact is leukemia, which is estimated that around 1 million people affected around the world and four types of leukemia diagnosed in their lifetime risk on exposure to 1 mg/m3 of benzene concentration.[15] In the occupational setting, health impacts of BTX are well known in oil industry. Association of BTX with cancer was proved in different studies.[16],[17],[18]
A Saudi Arabia national law stipulates that benzene level in the fuel not exceed than 1 ppm per liter. The study sample was collected for finding the concentrations of BTX (benzene, toluene, and xylenes) from 40 fuel stations and to determine the expected health risks on the human being for exposure of BTX by using HQ.
Material and Methods | |  |
Study settings and study design
This is the cross-sectional study and forty petroleum fuel stations were randomly selected, 20 samples each from the city of Dammam and Khobar. Each station has residential, traffic intersection, and station area for measuring the concentration of BTX. through simple random sampling [Figure 1].
Risk assessment
Benzene inhalation was calculated through United State Envrionment Protection Agency’s (USEPA) condtions for occupational exposure. Exposure duration (ED) and exposure frequency (EF) values were derived from interview data and the inhalation uptake of 50% of all intake [exposure concentration (EC)]. Exposure was done by the calculation of inhalation intake (EC) at concentration of inhaled air benzene as the following formula: EC = exposure concentration or intake (μg/m3)
EC = (CA × ET × EF × ED)/AT
CA = benzene concentration (μg/m3)
ET = exposure time, hours/day = 8 h/day or longer exposure time depending on individual data of workers
EF = exposure frequency (5 days/week × 50 weeks/year) =250 days/year guided by the USEPA. ED = exposure duration (25 years), AT = averaging time = average time in hours per exposure period (25 years for general working period is equivalent to 219,150 h) and 70 years for lifetime cancer risk characterization (70 years × 365 days/year × 24 h/day = 613,200 h) guided by the USEPA[19]
Cancer risk characterization by comparison to inhalation unit cancer risk (IUR) was considered as the following: Cancer risk = IUR × EC
where IUR = 2.2 × 10 −6 to 7.8 × 10 −6 per 1 μg/m3
If the risk value > IUR or 2.2 × 10 −6 to 7.8 × 10 −6, that means an unacceptable risk concerning cancer.
If the risk value <2.2 × 10 −6, that means an acceptable risk of cancer.
Non-cancer risk assessment is considered as the Hazard Quotients (HQ) calculation of non-cancer risk from chronic exposure to inhaled benzene, which was calculated by following the USEPA[19]
HQ (unitless) = EC/RfC
EC (μg/m3) = exposure concentration in air
Reference concentration (RfC) of benzene is 0.03 mg/m3 from the USEPA-IRIS.
Sampling and measurements
The concentration of BTX in air was checked during day work. Samples were collected at 1.5 m above ground about 2–3 m from the fuel pump by active sampling with a flow rate of 100 ml/min using SKC battery-operated air sampling pump model PCXR. The stratified random sampling was used for selection of fuel stations. BTX concentration levels were measured by using standard calibrated instrument. MIRAN SapphIRe Portable Ambient Analyzer was used for measuring BTX (Benzene, Toluene and Xylene).[18] It is placed at 1.5 m height. LOD ranges from 0.05 to 0.07 microgL (-1) and relative standard deviation ranges from 0.5% to 11.6% at concentrations 5 and 0.1 microgL (-1), respectively.
Data analysis was done on statistical packaging social science (SPSS) software. Results were presented in frequency tables. Descriptive statics, independent comparison T-test, correlation, and graphical presentation were used for data presentation. A hazard quotient (HQ) was calculated, which is the indicator of health hazard to the community. A value of hazard quotient (HQ) ≥1 indicates the risk of carcinogenic probability and value <1 indicates safe level.[19]
Results | |  |
The mean concentration of BTX was found in the cities of Dammam and Khobar: benzene 10.3 (SD 2.5) (benzene TLV 0.5 ppm), toluene 4.09 (SD 2.1) (toluene TLV 20 ppm), and Xylene 2.47(SD 1.7) (Xylene TLV 100 ppm). Both toluene and xylene were within the normal TLV, but benzene found excessive allowed TLV in both cities; significant differences were found between the levels of toluene and xylene among fuel petrol stations in Dammam in comparison with Khobar fuel stations [Table 1], [Figure 2]. | Table 1: The Concentration of benzene, toluene, and xylene (BTEX) in fuel station
Click here to view |
 | Figure 2: Concentration of benzene, toluene, and xylene (BTX) in all selected fuel petrol stations at Dammam and Khobar cities
Click here to view |
Mean levels of BTX [Table 2] concentration were found from petrol stations located at the residential area [8.0 ppm (SD 3.1)], side streets [12.2 ppm (SD 1.9)], and direct street [11.5 ppm (SD 1.3)] in Dammam and Khober. Benzene concentrations in all sites were found to be exceeding the TLV (0.5 ppm), while mean concentrations of Toluene and Xylene were within the TLV (20 ppm and 100 ppm, respectively) in all selected sites. | Table 2: The concentration of benzene, toluene, and xylene (BTEX) in different sites adjacent to fuel stations in cities of Dammam and Khobar
Click here to view |
Mean difference of BTX [Table 3] concentration among different sites and P value show a statistically significant difference. | Table 3: Concentration of benzene, toluene, and xylene (BTEX) in different areas of fuel stations at Khobar city
Click here to view |
The evaluation of the hazard quotient (HQ) [Table 4] for BTX among different sites shows that there is risk of carcinogenic effect to the nearby community living near to fuel station.
In the mean difference of meteorological factors such as [Table 5] temperature, humidity, and wind speed around the fuel stations, only wind speed was statistically significant (P value < 0.05). | Table 5: Comparison between mean levels of meteorological factor in fuel stations located in side street and direct street
Click here to view |
Discussion | |  |
The results of the present study show that the concentration levels of benzene, toluene, ethylbenzene, and xylene in both cities were high at fuel station and around the fuel stations. Hazards quotient value indicated that there is a risk probability of cancers to nearby living population.
The result of this study found that concentration of benzene (10.30 ± 1.88 ppm) was high in environment compared to standard limit (0.5 ppm over 8-h exposure)[20] which is standard by USA Occupational Safety and Health Administration (OSHA) and the American Conference of Governmental Industrial Hygiene (ACGIH).[21]
Previous studies found that mean concentration levels of benzene, toluene, and xylenes were high in Thailand,[22] Brazil,[23] and northern India.[24]
Hazard ratio in this study found greater than 1, which indicates the increased risk of cancer and also highlights the increased potential toxic and carcinogenic risks to which the people in the eastern province exposed to through toxic compounds of fuel such as BTX and its alkyl derivatives, which are harmful to human health because of their toxic, mutagenic, or carcinogenic properties; the same results were produced by the previous study.[25] These results were consistent with the previous study conducted in north India[26] and in Brazil.[27]
The relationships between the overall concentrations of BTX and traffic volume were found to be cofactors for elevated values for BTX in fuel petrol stations in both Dammam and Khobar. Similar studies conducted in Algeria and Brazil indicated that the levels of BTX and air pollution gases may be also affected by the atmospheric condition, the traffic density, and different activities in gas stations.[28],[29]
In addition, the National Institute for Occupational Safety and Health (NIOSH)-issued guidelines for BTX As 0.1,100 and 100 ppm respectively.[22] These findings are in accordance with recent studies which revealed that apart from the increasing vehicular traffic, another major cause of worry is unacceptably high concentrations of air quality gases and BTX in and around refueling stations.[23],[24]
The presence of BTX in the fuel/gas products is a high risk for human health specifically benzene compounds.[25] The results of this study found that benzene concentration present in the fuel/gas products was higher than the standard level.
Conclusion | |  |
The results of this study showed that BTX concentrations in the ambient air of fuel stations were higher than the average values in fuel station areas and near to fuel satiation areas, and HQ values were also greater than 1 which showed that the risk probability of cancer among resident was high. Therefore, effective intervention is needed to prevent harmful health effects.
Acknowledgement
I should extend my sincere appreciation to the Department of Public Health, Imam Abdulrahman Bin Faisal University, for provision of the necessary support that enabled me to fulfill this study.
Ethical approval and Consent to participate
The study was approved by Imam Abdul Rehman Bin Faisal University Ethical Committee, Saudi Arabia. The ethical document no is 2345.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
References | |  |
1. | Ukpaka CP, Abowei FM, Okerie U. Evaluation of Biostimulation rate of BTEX compounds of contaminated site. Multidiscip J Res Dev 2009;12:114-20. |
2. | Gauderman WJ, Vora H, McConnell R, Berhane K, Gilliland F, Thomas D, et al. Effect of exposure to traffic on lung development from 10 to 18 years of age: A cohort study. Lancet 2014;369:571-7. |
3. | Hinwood AL, Rodriguez C, Runnion T, Farrar D, Murray F, Horton A, et al. Risk factors for increased BTEX exposure in four Australian cities. Chemosphere 2007;66:533-41. |
4. | Symanski E, Stock TH, Tee PG, Chan W. Demographic, residential, and behavioral determinants of elevated exposures to benzene, toluene, ethylbenzene, and xylenes among the U.S. population: Results from 1999-2000 NHANES. J Toxicol Environ Health A ;72:915-24. |
5. | Caselli M, de Gennaro G, Marzocca A, Trizio L, Tutino M. Assessment of the impact of the vehicular traffic on BTEX concentration in ring roads in urban areas of Bari (Italy). Chemosphere 2010;81:306-11. |
6. | Sergio MC, Graciela A, Monica RC, Katia MP. The impact of BTEX emissions from gas stations into the atmosphere. Atmos Pollut Res 2012;3:163-9. |
7. | Cagliari J, Fedrizzi F, Finotti AR, Teixeira CE, Do Nascimento I. Volatilization of monoaromatic compounds (benzene, toluene, and xylenes; BTX) from gasoline: Effect of the ethanol. Environ Toxicol Chem 2010;29:808-12. |
8. | ACGIH. TLVs and BEIs. Based on the documentation of the threshold limit values for chemical substances and physical agents and biological exposure indices. Cincinnati, OH, USA, 2010. p. 13-29. |
9. | Majumdar D, Dutta C, Mukherjee AK, Sen S. Source apportionment of VOCs at the petrol pumps in Kolkata, India; Exposure of workers and assessment of associated health risk. Transp Res D: Trans Environ 2008;13:524-30. |
10. | Esteve-Turrillas FA, Pastor A, de la Guardia M. Assessing air quality inside vehicles and at filling stations by monitoring benzene, toluene, ethylbenzene and xylenes with the use of semipermeable devices. Anal Chim Acta 2007;593:108-16. |
11. | Sandhya C, Ashok K. Monitoring of benzene, toluene, ethylbenzene and xylene (BTEX) concentrations in ambient air in Firozabad, India. Int Arch Appl Sci Technol 2012;3:92-6. |
12. | Hoffmann B, Moebus S, Mohlenkamp S, Stang A, Lehmann N, Dragano N, et al. Residential exposure to traffic is associated with coronary atherosclerosis. Circulation 2007;116:489-96. |
13. | Hein R, Aung BT, Lwin O, Zaidi SH. Assessment of occupational benzene exposure in petrol filling stations at Rangoon. Ann Occup Hyg 1989;33:133-6. |
14. | Chauhan SK, Saini N, Yadav VB. Recent trends of volatile organic compounds in ambient air and its health impacts: A review. Int J Technol Res Eng 2014;1:667-78. |
15. | World Health Organisation. IARC: Diesel engine exhaust arcinogenic. In: IARC Monographs on the Evaluation of Carcinogenic Risks to Humans. Lyon, France: International Agency for Research on Cancer; 2012. p. 105. |
16. | Johnson ES, Langard S, Lin YS. A critique of benzene exposure in the general population. Sci Total Environ 2007;374:183-98. |
17. | Veraldi A, Costantini AS, Bolejack V, Miligi L, Vineis P, van Loveren H. Immunotoxic effects of chemicals: A matrix for occupational and environmental epidemiological studies. Am J Ind Med 2006;49:1046-55. |
18. | Office of Superfund Remediation and Technology Innovation Environmental Protection Agency. Risk Assessment Guidance for Superfund Volume I: Human Health Evaluation Manual (Part F, Supplemental Guidance for Inhalation Risk Assessment). Washington, DC, USA: Office of Superfund Remediation and Technology Innovation Environmental Protection Agency; 2009. |
19. | United States Environmental Protection Agency. Human Health Evaluation Manual, Supplement Guidance: Update of Standard Default Exposure Factors. Washington, DC, USA: United States Environmental Protection Agency; 2014. |
20. | Zabiegala B, Urbanowicz M, Szymanska K, Namiesnik J. Application of passive sampling technique for monitoring of BTEX concentration in urban air: Field comparison of different types of passive samplers. J Chromatogr Sci 2010;48:167-75. |
21. | Chanvaivit S, Navasumrit P, Hunsonti P. Exposure assessment of benzene in Thai workers, DNA-repair capacity and influence of genetic polymorphisms. Mutat Res 2007;626:79-87. |
22. | De Oliveira K, Martins E, Arbilla G. Exposure to volatile organic compounds in an ethanol and gasoline service station. Bull Environ Contam Toxicol 2007;79:237-41. |
23. | Edokpolo B, Yu QJ, Connell D. Health risk assessment of ambient air concentrations of benzene, toluene and xylene (BTX) in service station environments. Int J Environ Res Public Health 2014;11:6354-74. |
24. | |
25. | Saxena P, Ghosh C. Review of assessment of benzene, toluene, ethylbenzene and xylene (BTEX) concentration in urban atmosphere of Delhi. Int J Phys Sci 2012;7:850-60. |
26. | Pandey AK, Bajpayee M, Parmar D, Kumar R, Rastogi SK, Mathur N, et al. Multipronged evaluation of genotoxicity in Indian petrol-pump workers. Environ Mol Mutagen 2008;49:695-707. |
27. | Moro AM, Charão MF, Brucker N, Durgante J, Baierle M, Bubols G, et al. Genotoxicity and oxidative stress in gasoline station attendants. Mutat Res 2013;754:63-70. |
28. | Kerbachi R, Boughedaoui M, Bounoua L, Keddam M. Ambient air pollution by aromatic hydrocarbons in Algiers. Atmos Environ 2006;40:3995-4003. |
29. | Cruz LPS, Alves LP, Santos AVS, Esteves MB, Gomes IVS, Nunes LSS. Assessment of BTEX concentrations in air ambient of gas stations using passive sampling and the health risks for workers. J Environ Prot 2017;8:12-25. |
[Figure 1], [Figure 2]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]
|